Improvement in drawing-implements



W. SMITH.

Drawing Implements.

Patented July 14, 1874.

N o. l5 2 9 2 2.

UNITED STATES PATENT OFFICE.

WALTER SMITH, OF BOSTON, MASSACHUSETTS, ASSIGNOR OF ONE-HALF TO ABNER It. CAMPBELL, OF SAME PLACE.

IMPROVEMENT IN DRAWING-IMPLEMENTS.

Specification forming part of Letters Patent No. 152,922, dated July 14, 1874; application filed November 28,1873.

To all lwhom it may concern:

Be it known that I, WALTER SMITH, of Boston, in the county of Suffolk and State of Massachusetts, have invented a new and Improved Drawing-Implement; and I do hereby declare that the following is a full and exact description of the same, reference being had to the accompanying drawings and to the letters of reference marked thereon.

This invention is a new drawing-implement, which, from its construction and peculiar arrangement of marks and lines, is adapted to be used in the place of a number of separate instruments, as will be fully described herein after.

In the drawings, Figure 1 represents a plan view of my improved implement.

To enable others skilled in the art to make and use my invention, l will now proceed to describe fully the construction of the same, and the arrangement of its marks and lines.

A represents my improved implement, constructed of any suitable material and any proper size, which, in form, resembles the drafting-implement known as the triangle. It is provided `upon the outer edges of its three sides with division marks and numbers indieatin g its length in inches, each inch measure being subdivided into fractions of the inch,

one side being divided into thirds, sixths, and twelfths, another into iifths and tenths, and the other into halves, fourths, and eighths.

The inner edges of the sides forming the apex of the triangle are provided with division lines and numbers corresponding to'those upon a protractor of the ordinary construction, the inner edge of the base of the triangle having divisions and numbers forming ythe chordscale for a circle of three hundred and sixty degrees.

By means of the described construction and arrangement of division lines and numbers, my improved implement may be used in place of a rule, set-square, scale, protractor, and T- square. It is more convenient for use than the separate instruments, for which it is substituted, is not easily lost or misplaced, and is of course much less expensive.

This implement may be made of any proper material; but for certain purposes I prefer to make it of paper, as it can be produced at a triing cost.

Having thus fully described my invention, what Iclaim as new, and desire to secure by Letters Patent, is-

As a new article of manufacture, the drawing-implement formed of two sides of a square connected by a diagonal, the outer edges provided with various scales, and the inner with a scale of angles, forming in one implement a square, triangle, and protractor, substantially as described. Y

This specification signed and witnessed this 1st day of November, 1873.

WALTER SMITH.

Witnesses:

MARGARET HOWLETT, BENJ. DEAN. 

